Periodic and Bursting pH Oscillations in an Enzyme Model Reaction
-
Marcus J. B. Hauser
Oscillatory behaviour in the pH value was observed during the oxidation of sulfite by hydrogen peroxide mediated by hemin in a continuous-flow stirred tank reactor. The dynamics of this reaction was studied for a variety of flow rates of the reactants. As the flow rates increase, the oscillations evolve from relaxation oscillations to more complex shapes, displaying, among others, bursting behaviour. A reaction mechanism is proposed that involves the autocatalytic oxidation of HSO3- by H2O2, while equilibria between pH-dependent forms of hemin account for the consumption of protons. These equilibria provide the feedback steps which give rise to oscillatory dynamics. The contributions of the individual H+-consuming reactions to the dynamic behaviour are evaluated. Numerical simulations show that two pH-dependent reactions suffice to obtain bursting oscillations which resemble those observed in the experiments.
Articles in the same Issue
- Vibrational Dynamics in Hydrogen-Bonded (Pyridine + Water) Complexes Studied by Spectrally Resolved Femtosecond CARS
- Extending the Tuning Range of Short-Pulse Lasers by Transient Stimulated Raman Scattering in Gases
- Applications of the Karhunen-Loève Decomposition to Quantum Dynamical Problems
- Intramolecular Photoinduced Electron Transfer in Zwitterionic Quinolinium Dyes – Experimental and Theoretical Studies
- Probing Ethanol-Induced Phospholipid Phase Transitions by the Polarity Sensitive Fluorescence Probes Prodan and Patman
- Effects of Statistical Fluctuations in a Model of Tropospheric Chemistry
- Absence of Dual Fluorescence in Cyano Isomers and Di-Cyano Derivatives Related to N,N-Dimethyl-4-Aminobenzonitril: A DFT/MRCI Study
- Periodic and Bursting pH Oscillations in an Enzyme Model Reaction
- Book Reviews
Articles in the same Issue
- Vibrational Dynamics in Hydrogen-Bonded (Pyridine + Water) Complexes Studied by Spectrally Resolved Femtosecond CARS
- Extending the Tuning Range of Short-Pulse Lasers by Transient Stimulated Raman Scattering in Gases
- Applications of the Karhunen-Loève Decomposition to Quantum Dynamical Problems
- Intramolecular Photoinduced Electron Transfer in Zwitterionic Quinolinium Dyes – Experimental and Theoretical Studies
- Probing Ethanol-Induced Phospholipid Phase Transitions by the Polarity Sensitive Fluorescence Probes Prodan and Patman
- Effects of Statistical Fluctuations in a Model of Tropospheric Chemistry
- Absence of Dual Fluorescence in Cyano Isomers and Di-Cyano Derivatives Related to N,N-Dimethyl-4-Aminobenzonitril: A DFT/MRCI Study
- Periodic and Bursting pH Oscillations in an Enzyme Model Reaction
- Book Reviews
